TORONTO, JAN. 26 -- Robert Campeau, the Canadian raider who is bidding $4.2 billion for Federated Department Stores Inc., said today he does not plan a major dismemberment of the company's 15 divisions if he succeeds in his hostile takeover.

The chairman of Campeau Corp. said he eventually would merge Federated with his Allied Stores Corp., a move analysts said would create America's largest department store chain, with glamorous names such as Bloomingdale's and Brooks Brothers in its portfolio.

Campeau, who acquired Allied for $3.5 billion in a 1986 hostile takeover and later dismembered the retailer, selling Washington-based Garfinckel's and several other chains, would not comment on speculation that he would be forced to sweeten his $47-a-share bid for Cincinnati-based Federated.

Meanwhile, Federated filed suit in Franklin County Common Pleas Court in Columbus, Ohio, asking the court to declare Ohio's Takeover Act constitutional and applicable in the Campeau bid.

On Monday, Campeau began court actions in three states to overturn antitakeover statutes, a spokeswoman for the Toronto company said. It also sued Federated in federal court in New York, seeking to invalidate the company's poison-pill antitakeover defense.

Analysts said a bidding contest could push the cost of Federated stock to at least $55. But Campeau said, "The analysts are not bidding. ... We have an offer there, and the offer is there."

Campeau said he planned no widespread sales, although analysts said Campeau could sell some of Federated's valuable real estate.

"Obviously this is not a company that has a lot of divisions to be sold," Campeau said. "We've made our decision to buy Federated to further our retail business."

Federated operates 10 department store divisions, one mass merchandising division, one supermarket division and three specialty store divisions.